Brass-melting apparatus



June 2, 1931. A. w. MAcHLET BRASS MELTING APPARATUS Filed July l0, 1929 2 Sheets-Sheet l un ...www UGH UWIIII. .1//l

/m/m fa June 2, 1931. A. w. MACHLET BRASS MELTING' APPARATUS 2 Sheets-Sheet 2 Filed July 10, 1929 30 expenditure of fuel than is .Patented June 2, 1931 Anonrn w. Maenner, or ntrznnn'rn, NEW JnRsEY i BRASS-IQELTING APPARATUS Application filed July 10,

This invention relates to improved means lfor melting brass. e v Since the melting point of brass is extremely high, and since in order to -malre 15 satisfactory brass castings it is necessary to superheat the melted brass to about 2100o or 2200o so that it can be poured satisfactorily, it has been customaryto use melting pots formed of a composition of graphite or clay.

l .These materials are poor conductors, and the cost of fuel mounts very high.

In aiming to economize heat, it has been the practice to employ many different sizes and forms of pots, for melting different l quantities of brass, always using the smallest possible Crucible for the work in hand. The Crucible soon perishes from exposure to the extreme heat.

If it is sought to melt the brass in an ordinary pot of metaL-it is found that it cannot withstand high heat as successfully as a graphite Crucible, and the danger is inincurred that superheating of the brass in the metal pot would resultoin melting the 25 metal pot itself. However, a metal pot or -crucible is a desideratum because ofits high' conducivity vand economy in fuel. According to the present invention, the brass is melted and superheated with less than half the necessary when using a graphite Crucible. The difhculty and danger of melting the metal pot may be avoided by employing for the -pot a certain metaltube having ends ofrecalcitrant material, and keepingV the tube in steady, slow revolution, so that it cannot become overexposed to heat at any point, thereby avoiding melting or softening of the tube. VThe crucible may be made in the form of a barrel, o bottle or hollow cylinder, which may extend in cumbent position for convenience in charging and discharging; and the heat may be ap-y plied to the heat-absorbing top of the tube or barrel, remote from the work therein, where- 5 bythe top becomes very readily heated and upon revolution reaches a bottom position, where it contacts with the deposited metal therein and'melts the same. Owing to the conductivity of the bottle, brass Amelting is 5 effected economically.v The Crucible may be 1929. Serial No. 377,105.

made of considerable length in proportion to its diameter, whereby the heat is'utilized to thebest advantage, inasmuch as a long thin body or heap of work-metal is more accessible to the heatz and more readily melted, anda relatively long metal Crucible of relatively small' diameter is more efficient in melting the work-metal than is the standard relatively short-*metal pot of great diameter. The metal bottle has the advantage that it is not apt to amalgamate with the copper or the zinc of which the brass is formed.

The metal poter crucible is preferably given the form of a bottle, and can be mounted for tilting, and it can berotated on its o5 longitudinal axis, and gas flames may bearranged to play upon the bottle as it rotates. Then it may be turned upon its trunnions to decant the melted brass; the Crucible or bottle being mounted in a gas -furnace to tilt there'- 70 with, under the cont-rol of the operator. The liereinclescribed bottle may survive about twice as many beatings as an ordinary graphite pot; and when worn out it maybe readily detached from its mountings and replaced by 7 5 a fresh bottle. A

The same Crucible, because of its constant revolution, may economicallyvmelt either a large or a small quantity of brass. The invention is very liexible in meeting the differso ent practical requirements, as compared with a graphite melting pot of standard manufacture. f y Y rThe metal bottle is heated by means of a` flame of mixed fuel-gas andv compressed air, which is advantageously applied to the top portion of the revolving bottle, and substantial reduction in the cost of brass vmelting is effected, as compared with standard practice.

- Thus a metal Crucible may be employed in the form ofl a revolving pot ory bottle, havinga high degree of conductivity, as -compared with standard graphite crucibles. This economy is rendered practicable by the rotation of the Crucible, since the'iiame does 95 l. not impinge long enough againstone point of the revolving bottle to melt or soften the same. This solves the problem of supplying heat to melt brassy without melting the metal pot. While the` revolution of the crucible I Y bottle-neck projects.

sure ofthe gas upon the Work will be such e that the vapor-ization point of zinc will be raised. The Crucible is sealedV at its mouth so as to retain the volatilized zinc under pressure.

It is further sought by the presentfinvention to facilitate the charging of'a Crucible, and to facilitate, quickenand Cheapen the meltingof brassjto bring the heat during the whole operation under better control than has heretofore been found practicable, and to overcome other difficulties in brass melting.

' There must be an element used in the furnace as part of a heat-regulating device, as the furnace must be guarded very carefully against overheating, which would result in the melting of the pot. Theelement is put into thevbottom of the furnace below the retort where the flame Cannot touch it. The difference is very slight between the melting point of the pot and the point to which the melted brass has tobe heated. j Preferably the Crucible is in the form of a cast bottle formed ofan allow Consisting of Y iron and chromium.v This bottle has a bot-V tom or closed end from which extends a stem or. hub which is cast integral with the bottle, and is of small diameter, and projects through the wall of the furnace. By reason of its small dimensions it wastes very litt-le heatv by radiation outside of the furnace. Moreover, it permits the use of a small hole in the furnace-wall so as to avoid loss'of heat through the crevice in V which the stem revolves. Y

The lbottle is made relatively thin and long, say 9 inches in diameter and 3 or 1 feet long.

At the other end the bottle is reduced in diameter and formed with a neck and mouth, the ldiameter of the neck being about 6 inches and extendingthrough a hole in the Vopposite wall ofthe furnace. Y y In thefurnace is provided a removable section Containingthehole through which the This collar is removable, to permit withdrawal of the'bottle from the furnace; A e

Other features and advantages will hereinafter appear. j Y ,Y

In the accompanying drawings, Figurey l is'a sectional longitudinal eleva- Vtiovny'of theprcferred form of'carrying out the f invention, a level working position of theV melting bottle being shown by full lines, and a tilted position in ydot-and-dash lines. .The bottle may be decanted downwardly to discharge the melted brass.

Figure 2 is an elevation of the driving end y of the furnace.

VFigure 3 is a section through line 3--3 of Figure 1, showing the arrangement'of the meltingvbottle in the furnace, and the preferred arrangement 4of burners, and also showing the element of the pyrometer.

Figure 4 is a plan of the furnace and appurtenances, partly in section.

' A cylindrical furnace 10 is journaled between its ends by means of gudgeons 11 upon a supporting Vframework 12. A heating chamber 13 extends from end to end of the furnace, and contains a brass-melting pot, preferably in the form of' a bottle 14; which revolves within the Chamber 13. A`The bottle maybe of cylindrical lform and occupy a position near the bottom of the heating chamber, inthe top of which may beplaced oppositely directed burners 15 for mixed gas and Compressed'air, as seen in Figure 3, the flames impinging upon the top of the melting bottle, which, because yof its continuous revolution, does not at any place remain exposed to the pre-heating ofthe flame very Y long, and therefore does not'soften nor melt.

VvBy reason of the revolution, the pre-heated portion of the bottle revolves from top to bottom, where it comes in Contact with the work in the bottle The work-absorbs the heat from the wall of the bottle and nopart of thebottle is pre-heated much above the brass-melting point,rand hence .the bottle remains intact. The heating may be effected by other combustibles, or by an electric heaty,

ing furnace equipment. Y j

VThe bottle is supported for revolutionv outside of the ends of the furnace on rolls16, 17 at one end, andv18, 19 at the other end.

- The closed end of the bottle may be spheroidal A or dome-like, as at 20, and from this end projects a stem or gudgeon 21 through a small opening 22 in the end wall 23 of the furnace. This stem 21 Vterminates in a-reduced axle-portion 24,-` upon which is fixed a hub 25, having a circular tread 26 toride upon the rolls 16,Y 17 g a driving sprocket 27 ,being secured to this hub for rotating the bottle. The diameter of the hole 22 is only very slightly larger than the diameter-of `V120 the stem 21, so as 13o-minimize' the waste of heat'from the furnace.Vv j

Iheother end of the bottle is reduced at 28. and 4is formed with a neck in the form of a hollow V,trunnion 29, which projectsy through the end of the furnace and rides directly upon the supporting rolls 18, 19.

In order to charge the melting bottle, the

upon the'bottle maybe lowered to the desired ics position,y vand heated by burning Va mixture of gas and air delivered from the burners l5. If only a small quantity of brass is being melted, the bottle may maintain a horizontal position, as at Figure 1, since ythe'reduced DuringA the melting, .the Crucible-heating flames flow in opposite transverse directions from the burnersacross the top and down around the sides of the bottle; and thev supply of fuel is controlled, so that the crucible or bottle will be exposed to no more heat than can be readily'taken up by the melting brass, Vso as to avoid undue heating and therefore and possibility of softening or melting of the bottle itself before its h-eat can be imparted to the work. The bottle being placed inthe lower part of the furnace, Figure 3, receives most of the heat at its top portion, and its `temperature is lowered as the bottle re volves and thel heated part comes in contact with the brass, which is indicated at 3l.

The bottle, with the stem 21, axle-portion 24:,neck 29 and mouthing 30, consists of one piece or a single casting. The bottle or crucible is made of an alloy which successfully resists the superheat to which it is necessary to raise the melted brass after it has been melted, before it canbe poured successfully.

This alloy consists of iron and chromium. The proportions are about 05% iron and 35% chromium. The iron 'is .65 carbon. For melting some alloys, the Crucible may be made at iron, 27% chromium and 8% nickel. The melting point of the Crucible is about 2400o or a little more, which is sufficiently high for practical purposes above the heat of2200o to which the, melted brass must be superheated before pouring. The melting point of brass is 1900", but the melted brass has to be superheated up to 2100", so that it can be poured successfully into moulds, because it is too sluggishrfor that purpose when it is barely melted. Sometimes the heat Yof the melted mass runs up to 22000, or Within200O of melting the Crucible itself. The dierence is very slight between the `vmelting point of the Crucible and the highest `point to which it is necessary to melt the brass in order to pour it. a

It will be understood that the use of a metal pot for brass melting has not heretofore been found feasible, because the brass has to be'superheated after melting, and consequently the metal pot itself would be apt to soften and melt from the heat; the melting point of `the metal pot being only aY trifle hio'her than the point to which it 1s necessary to superheat theinelted brass. It is moreover impracticable to guard against over#V heating a metal pot, under the circumstances.

Ythe furnace-Wall. llength and small diameter, to .exposey the Infaddition, the metal of the pot would be aptto amalgamate with the brass, or Vwith one of the constituents of the brass; and the amalgamation of the pot with the brass would lower the 'melting point of the-potritself, so that melting of the material of the metal pot would be practically"unavoidable. l

It will be perceived that these difficulties have been overcome by the present invention. One of the important features of the inventionv is the provision of means whereby the metal pot or Crucible can be safeguarded against melting. To this end the heat is supplied to .the pot or Crucible at a point .remote lfrom the point where the brass is being melted, `and a pyroineter element is inserted in the furnace at a point remote vfrom the point where the flames 'are generated. The pyrometer tells what is the `heat in the furnace-chamber at that remote point, which information is found practically sufficient forthe purpose of regulating the heat of the crucible to keep it below the softening point. This.heatcontrol is rendered feasible bycontinually lrevolving the Crucible, so that the portion vthereof that is pre-heated by vthe flames isslowly brought into contact with the brass, which is gradually melted and super heated; Y

The chromium does not amalgamate with the zinc nor the copper, nor does the iron.

This alloy has sufficient strength sothat crucibles. Vrl he meta-l has quite high conductivity, in that it readily absorbsthe. heat from the furnace, and readily imparts the same to the brass-work.

The stem'on the bottom `ofthe bottle-is to save the heat. It reduces the extent to- 'which heat is wasted by radiation outside of the furnace, and permits the use of a small hole in The bottle has great melt-ing brass advantageously to the attack of heat. *There is but little liability of bending of the heated crucible or-bottle. The rotation of the vbottle prevents the flame from overheating andsoftening and perhaps melting, all of which might occur if` the bottle were kept stationary, especialy if flames were applied to the top thereof, as shown. The stem is three inches in diameter. The neck of the bottle is 6 inches in diameter.

It will be seen that a great saving of fuel is effected by reducing bot-h projecting ends of the bottle, so as to reduce correspondingly the holes in ,the furnace-walls, andhave the neck ofthe bottle only large enough to permit the charging. i y

is Y

After the: work'is in place, a cover 32V is level position, as-at Figure 1, or be swung to an upwardly-inclined position, according to the quantity of work in the bottle.- The inclined bottle holds more work. The tilting of thefurnace is elfected by a crank 37, driving bevel gears 38,. 39, the latter operating a worm 40which turns a worm-wheel 41 provided upon one of the furnace-gudgeons 11.

The bottle 14 is given a slow revolution bvV means of a motor 42, having a drive-chain connection to a movement-reducing. chest 43, thedelivery shaft 44 of which rotates slowly.

Upon the shaft 44 is abevel pinion 45, meshing with a pinion 46-upon a shaft 47, which Carries a sprocket 48, connected by a chain 49 to the sprocket 27 upon the aXle 24 ofthe work bottle or Crucible. l A

The bottle turns upon the rolls 1,6-19, and when the furnace is tilted up, the weight of the Vwork bottle or crucible is partly supported by meansv of abearing provided in an arm 50 secured by bolts 5l on the wall of the furnace. To relieve fric-tion, there is provided a circular row of bearing balls 52, which run in grooves formed in a pair of washers or collars 53 whichare placed upon a nipple 54, projecting from vthe, end of -the* bottle-axle 24.

The .Crucible is--lrept from melting'by the aid of a heat-regulating device which includes a pyrometer having'an element 55a extending through` an orifice 56 through the wall. of the furnace, and terminating in the bottom part of the flame-chamber where the heat is least. After the meltedv metal has been heated to the proper point for pouring, the flames are shut olf, and the crank 37 is revolvedto rock thefu'rnace down to decanting position, the cap 32 having been removed. The shoulders 28 enablerthe bottle to retain a fair quantity of melted metal while 'the bottle is inlevel position, but the furnace does not have to'be tilted down very much in order .to discharge lthe entire contents of the bottle; outwardly or cone-'shapechfor convenience in both charging and discharging the bottle, and for realizing other advantages.

Vhen the furnace is tilted down, the bottle f 'is retained in position by means of a lflange The neclr57^of the 'bottle is flaredk 17 and holding the bottle against slipping when decanting. Y 'e j lVhen it is desired to remove the cruCibIe, a

sectionof the furnace-wall may be'removed,

leaving an opening largeV enough for takingy overcomingwaste of heat through the joint between the annular section and the furnacewall-itself. i If the section 59 is Vmade too small V.to slip over the Abrim 34 on the end of the bottle-neck, the section may b-ey made in segmental halves, which may be 'secured together to form a complete collar or annular section.- The brim 34 of the bottle-neck may, however, bemade s o small as to permit the collar 59 to be made in one pieceand slipped over the brim. This section'or collar may be of heat-resisting material, of a character used in building furnaces. The collar may be held in place by a series-of Vbuttons 62 loosely bolted at 63 to the iron-facing frame -64 of the furnace-end. Y

The use of very close apertures in the furnace-ends is permitted, by reason of the'exV pedient of adjusting the crucible at each end independently, so as to bring it to a true central position withintlie apertures 22 and 65.

This adjustment iseifected by means of setscrews 66, 67, Figure 2, threaded through lugs 68 formed iny the endwalls of the furnace. These set-screws support the upper ends of levers 69, 70 pivoted at 71 to the bottom of the furnace,"and provided with studs 72 upon which the-rolls 16-19 rotate. The levers 69,

70 diverge'upwardly and outwardly, so that if 'either set-screw is unscrewed, the levers 69 or70 will fall loutwardly toa corresponding extent, togetherewith the'rolls 16 vor 17, thereby lowering one end ofthe work-bottle,

By screwing upk the set-screws, the rolls may be raised one at a time. This gives universal adjustment of each end of the bottle up or down andto the right or left, at Figure 2.

This l readj ustment is a special convenience when replacing a wornout bottle with anew one, as the new bottle is very 'readily' centered. There is quick replacement without taking :down the furnace. It is only necessary to take out the collar and take offl a driving wheel. The furnace mayi include iron'end frame 'or wall 64, and an iron frame 7 3'for the opposite end, these end walls being joined by a cylindrical metalshell or-body 74, at-

tached to the ends by annular devices 75.

The shell 74 has a lining of asbestos 76, sur- .roundingblocks' which forma tubular body 77 of suitable heat-retaining substance. Within. the tubular body 7 7 is supported the firebrick body 78 of the furnace, having holes 79 for the burners 15, and having at its 5 ends the opening .22 for the stem 21 of the work-bottle, and having in the other end the circular-stepped opening 60, 61 for the removableannular section 59. The left-hand end of the furnace, Figure 1, may be provided with a sight-hole 80. f

It is often necessary, in producing a furnace, to trim od the ends of the furnace-body 78, so that it will fit between the iron endframes 64, 7 3. To overcome this difficulty, the furnace-body -78 is made under-length, and the discrepancy is made up by the use of packing disks or annular sheets S1 of asbestos, which readily close the gaps between the ends vof the furnace-body 7 S `and the iron frames or ends 64, 73. This aords provision for a certain range of variation in the length of the body or lining, and in the length of the furnace. The asbestos can be in sheets of 1/8 t'o 1/4 inch thickness, and may be packed in as required, to fill up the end spaces. These asbestos sheets make the ends tight, as both thin and thick ones may be packed in as re# quired, and no labor is required for trimming ofi' the end of the furnace-body or lining 7 8. In view of the exposure of the crucible to liability of melting under the high heat which is necessary, there is provided in the bottom of the furnace a large outlet 82, Vso that melted metal falling into the furnace may escape into a suitable receptacle that may be provided beneath the'outlet `82, and thereby avoid or minimize the damage lwhich the hotcmetal might effect.

Variations may be resorted to within the v"40 scope of the invention, and portions of the improvements maybe used without others. Having thus described my invention, I cla-im:

1. A brass-melter including a liquid-tight f one-piece `crucible in the form of a .cumbent shouldered metal bottle, a furnace through which the ends of the metal'bottle protrude,

means exterior to the furnace upon which the klrevolving the bottle onits longitudinal axis,

and means for sealing the bottle, whereby pressure may generateV within the bottle to raise the boiling point of the melted metal.

2. Apparatus constructed according to y claim 1,. in which the sealing means includes a cover for the bottle, andvmeans for fastening the cover to the bottle, said cover having a pipe for supplying inert gas to the bottle.

3. A brass-melting crucible Lin the form of a revoluble liquid-tight one-piece cast ,m

bottle formed of analloy of iron and-chromium, the melting point of the crucible being about 24000, the proportions being substantially iron and 35% chromium,` and having at one end a shoulder terminating 51,5

in a neck, the shoulder co-operating with the bottom of the bottle and with the under side of the bottle to form a melting pot dur',- ing the revolution of the bottle when in cumbent position, said bottle having at its opposite end an integral gudgeon co-operative with the neck of the bottle to mount the bottle 'l 65% iron and 35% chromium, and having at one end a shoulder terminating in a neck, thel shoulder co-operating with the bottom of the bottle and with the under side of the bottom to form a meltingpot during the revolution of the bottle whenin cumbent position. Y

5. Abrassmelting crucible in the form of a revoluble liquid-tight one-piece cast'bottl'e formed of an alloy of iron and.' chromium, the meltingpoint of the crucible being about Y 2400, the proportions being. substantially 65% iron and 35% chromium,said bottle'be-Z` ing of a length of 3 or 4 feet, 'and a diameter of about 9 kinches and .havingv at onerend a shoulderl terminating in a neck, the shoulder co-operatinglwith the bottomjof the bottle and Withthe underside of the bottle toform "ice amelting pot duringtherevo'lution ofY the` bottle when in cumbent position. f

' 6. A brass-melting crucible in the form of a cumbent liquid-tight one-piece castA bottle formed of thespeciied alloy of iron and chromium, the melting point of the crucible being aboutv2'400o, the bottle not scaling off Vwhen exposed to brass-melting heat, and a perforated furnace enclosing said bottle, said bottle having an integral bottom or closed end and an integral gudgeon in the form of a hub protruding from said bottom to the eX'-v terior of the furnace and there provided with a hub-portion, rolls provided upon the exterior of thefurnace for supporting] Vilo said hub-portion, said hubfilling closely the perforation in the wall of the furnace, and. b e'ingabout 3 inches in diameter and said bottle having at its opposite end a shoulder and a reducedv neck, said neck about- 6 inches in diameter, the furnace having aJ hole in its ias wall to lfit closely about the neck of the: boti tl'e, and rolls on the outer side of the furnace to enable said neck partially to support thev bottle, the shoulder and bottom enabling the bottle to serve as a melting pot;

1 7. A crucible in the formof acast bottle, and a perforated furnace enclosing said bottle, said bottlehaving an integral bottom or closedend and an integral gudgeon in fthe form of a stem or hub protruding from said bottom to the exterior of the furnace and provided With'a hub portion, rolls provided upon theexterior of the Yfurnace 4for supporting said hub-portion, said hub being of very small 'diameter and fitting .closely in the'perforation inthe Wall of the furnace, said bottle having atone endza shoulder and a neck, the latter protruding` from the fur# nace and there supported ,on exterior rolls,

l said furnace having a removable section fitting about the neck of the bottle, to be removed to leave a space for removing the bottle, and means for fastening the section in place. in the furnace.

8. A brass-melting apparatus including a furnace mounted for tilting up or down and having perforationsin its opposite ends, a one-piece Vliquid-tight z brass-melting crucible of substantially the described'alloy, having a higher melting point than brass and not scaling off when subjected tobrass-melting heat, and in the form of a metal bottle Within the furnace and having gudgeons projecting through said perforations and. filling the Y same closely to minimize Waste of heat, ex-

v:as

confine the. melted terior rolls upon thezfurnace-Walls to sup- A port, said gudgeons for rotation, .oneof said gudgeons being hollow and forming the neck of .the bottle, the latter having a shoulder at said neck, to enable the bottle to operate as a melting pot when cumbent, saidv fur-i nace having means for heating said bottle at a section remote from the VWork, and-means outside of .theyfurn'ace for rotating said bottle. l 1

Y 9. A brass-meltingone-piece crucible in the form of a cast bottle formed of an alloy of iron, chromium andnickel, not amalga- `matingvvith melted brass, or scaling off when exposed to heat sufficient to meltbrass, the

a crucible in the formof a liquid-tight metal bottle'withinthe furnace and having gud geons ofk greatly reduceddiameter projecting through said perforations and filling the same closely to minimize Waste of heat, rolls upon-the exterionof the furnace-Walls to ling the crucible at each end up or down, and

supportfsaid fgu'dgeons for rotation, one of said gudgeons'being'hollow and forming the neck of the bottle, said 'furnace having ymeans for heating said bottle, and means outside ofthe furnace forrotatingfsaid bottle, said bottlevb'eing provided With a shoulder at the base of said neck for enablingv a quantity of melted metal to be retainedrin'theV bottle'to enable it'toiserve as a melting-pot While it is in level position', the neck ofthe bottle being flared outwardly from its base to its discharge end.l .f a l- 1l. A brass-melting crucible in the form of a cast bottle formed. of an alloy of iron and chromium, the melting point of the crucible being about 24000, Va perforated'furnaceenclosing said bottle, said bottle having an integral bottom and an integral gudgeon inthe form of a Vstem protruding from said bottom to the. exterior of the furnace and provided With a hub-portion, rolls provided upon the furnace for-supporting said hub-portion, said hub lbeing of .very

small diameter and fitting closely in the perforation in thewvall of the furnace, said bottle having a neck protruding from theV furnace and supported on exterior rolls, said furnace having* a removable section fitting about the-neck of the bottle, and means for fastening the section in place in the furnace, said removable section in the form of' an annulus,and'the furnace-Wall having a circup lar opening in which the annulus is fitted; said annulus having a stepped series of annular shoulders, and the furnace-Wall vprovided With'corresponding stepped annular seats', to

Vavoid VWaste Vof heat through the joint; said fastening means including a series of buttons loosely holding the section in place in `the furnace-L ji 12. Abr'ass-melting apparatus including a furnace mounted for tilting up or downV and having perforations in its opposite ends, a brass-melting crucible in the formof a metal bottle Within the furnace and having "gudgeons projecting through saidV perforations and filling the same closely to minimize Waste of heat, exterior rolls upon the furnace-Walls to support saidgudgeons for rotation, one of said gudgeons being hollow and Vforming the neck of the bottle, said furnace having means for heating said bottle, means outsideof the furnace for rotating said bottle, andv center# ing means outside of the furnace for adj ust;

also sidevvise, independently of the other end,

`so 'as to bring the crucible'to a true central position Within the'closely fitting apertures in the' furnacewalls, said centering means including set-screws provided in lugs in the end Walls of the furnace, and levers lbeing mount'-V ed at the outside of each end of the furnace and pivotally supported,v and having means Whereon the bottle-supporting rolls rotate,

said levers being adjustable by meansl of said set-screws, and diverging upwardly and outwardly so that by manipulating the screws the positions of the levers may be changed independently of one another, and the position of the bottle thereby corrected.

13. A furnace in which is mounted a revoluble wor -containing member which extends through the ends of the furnace and is provided outside the furnace with supporting and rotating means, said furnace including iron end frames, a cylindrical metal shell joining said end frames and attached thereto, gudgeons upon said shell for tilting the furnace, said shell lined with heat-retaining substance, a tubular body of fire-brick which is surrounded by said lining of heat-retaining substance, said body formed with ends having holes through which said work-containing member protrudes, said furnacebody being made under-length, and packing disks of asbestos closing the spaces between the ends of the under-length body and the iron end frames of the furnace.

14. A brass-melting Crucible in the form of a cast bott-le formed of an alloy of iron and chromium, the melting point of the Crucible being about 24000, a perforated furnace enclosingsaid bottle, said bottle having an integral bottom and an integral gudgeon in the form of a stein protruding from said bottom to the exterior of the furnace and provided with a hub-portion, rolls provided upon the furnace for supporting said hub-portion, said hub being of very small diameter and tting closely in the perforation in the wall of the furnace, said bottle having a neck protruding from the furnace and supported on exterior rolls, saidfurnace having a removable section fitting about the neck of the bottle, and means for fastening the section in place in the furnace, said removable section in the form of an annulus, and the furnace- Wall having a circular opening in which the annulus is fitted.

15. A brass-melting crucible in the form of a cast bottle formed of an alloy of iron and chromium, the melting point of the crucible being about 24000, a perforated furnace enclosing said bottle, said bottle having an integral bottom and an integral gudgeon in the form of a stem protruding from said bottom to the exterior of the furnace and provided With a hub-portion, rolls provided up-v on the furnace for supporting said hub-portion, said hub being of very small diameter and fitting closely in the perforation in the wall of the furnace, said bottle having a neck protruding from the furnace and supported on exterior rolls, said furnace havin a removable section iitting about the neck of the bottle, and means for fastening the section in place in the furnace, said removable section in the form of an annulus, and the furnacewall having a circular opening in which the the annulus is fitted; said annulus having a stepped series of annular shoulders, and the furnace-wall 'provided with corresponding stepped annular seats, to avoid waste of heat through the joint.

16. A metal-heating apparatus including a furnace mountedfor tilting up or down and having perforations in its opposite ends, a Work-receptacle liquid-tight within the furnace and having gudgeons rojecting through said perforations and lling the same closely to minimize Waste of heat, exterior rolls upon the furnace-walls to support said gudgeons for rotation, one of said gudgeons being hollow and forming the neck of the receptacle, said furnace havingvmeans for heating said receptacle, means outside of the furnace for rotating said receptacle, and centering means outside of the furnace for adjusting the receptacle at each end up or down, and also sidewise, independently of the other end, so as to 'bring the receptacle to a true central position within the closely fitting apertures inthe furnace-walls, said centering means including set-screws provided in lugs in the end walls of the furnace, and levers being mounted at the outside of each end of the furnace and pivotally supported, and having means whereon the receptacle-supporting rolls rotate, said levers being adjustable by f means of said set-screws, and diverging upwardly and outwardly so that by `manipulating the screws the positions of the levers may be changed independently of one another, and the position of the receptacle thereby corrected.

ADOLPH `W. MACHLET. 

